Angle dental handpiece



June 25, 1935. p, R, SK|NNER j 2,005,849

ANGLE DENTAL HANDPIECE 'Filed July 6, 1935 ATTORNEY Patented June 25,1935 v UNITED STATES PATENT OFFICE 'i v ANGLE DENTAL HANDPIECE Perry R.Skinner, Amsterdam,N. Y. Y Appuaaim July 6, 1938, serial No; 679,248 'Y7 claims.A (c1. svt- 27) This invention relates-to means for detachably.

securing a tool in operative position inl an angle;

tial groove in the rotating tool, or otherwise en.

gages the tool. Consequently, after anyconsiders able use, the.securingmeans becomes worn by reason of frictional Contact with thetool, thetool 15? is less rigidly held, and finallyl theseouring meansbecomes inoperative. Anyloosening of the tool in its holder allows ofmore orless wabbling of the tooland impairs its effectiveness, andfrequently in practice, because of thewearing out of the. attachingmeans, a tool is released in the mouth of a patientbeing operatedv upon,and there isdanger of lthe tool lodging in the throat. of the patient orof being swall owed.

One object of thepresentinvention.is yto pro.- vide means for-detachablysecuring a tool an angle dental zhandpiece, wherebywhen in .use .the

tool is directly secured to the driving means by which Vthe tooloperated, dispensing with any intermediate device upon which frictionisirn- 1 posed. Further-objects .areto provide .attaching means of thekind .described vin which a tool may be either secured 0.1' released byeasy and rapid manipulation of .the Aparts employed, 'and which isvadapted for use in: connection. with-.tools 351. having the standard.form ois Another .object is. to. provide means in which thepowerapplied-to rotate a tool, operatively located in a handpiece, shall beutile ized rto insure :z toolr against possibility of removal duringsuch rotation.

.The invention resides. .in Jthe.generically an specicallv novel.features 'of construction `'and relative arrangement of. `coacti'ng`Aparts substantially as hereinaIterKdes-cribed andclaimed. 45Thepresent illustration of theV invention shows one embodiment thereof,and anu-nderstanding of the principles of operation involved will makeit clear that the forms and aggroupments ci the elements .employedmayfvwidely "be varied without .departing from the. scope of inherentnovelty. I

In ,thedrawing; v VFigure 1 isa centr-e1 vertieaI sectional View of thehead of angle dental'handpiece, construct 5r .ed .in .accordance with.the invention, a toolfbeing ,tophettehine' shown introduced and inposition to be attached and retained by the rotation of the securing'-means. g

Figure 2 is a top plan view o f the handpiece. Figure 3 is a, sideviewofa dental tool having a 5 shank of standard form- Figure 4 is e side viewof. a rotatable' sleeve by which the tool-holding member of the vdev-ineis received and driven, the wall of the sleeveA being broken. @Wav Vtoshow a projection by which the 10 tool-holding Amember engaged, andWhith is adapted to secure a tool operative positions Figure 5 is asideview of the tool-receiving membet Figure 6 is a transverse sectionalview of the 151 tool-holding member, the section 'being takenon the line6 6 in Figure 5. Y j y Figure l is a transverse sectional viewv taken onthe line l-l' of Figure l. f Y Y In the form of the invention hereinillustrated, 2O the head or the angle dental handpiece is shown asconsisting of a shell composed oftwo separa.- ble parts 1y and 2, eachprovided with an exterf nally i screw threaded extension 3 (showrr bydotted lines in Figure Yl), which extensionsiare 2 receivedbyand-normally held in the interiorly` screw threaded portion 4 of ashaft casing. `By this construction ready separation ofthe parts toallow access to .the interior of` the head for purposes of repair,removal and substitution'of 30 parts, oiling, sterilizing, etc., lisprovided for. i

Mounted in the head of Ythe handpiece isy a rotatable ksleeve Y5 whichingeneral form corresponds to those commonly employed in similar struc-,tures, The `sleeve has on it a beveledgpal' with which meshes a. beveledpinion l on" the .endof a shaft 8 and'bv which rotation 0i the.sleeveand parts. connected is effected The shaft 8 .driven `in anysuitable way, as by the usual viiexible aft employed in this connection.Extending front-th '40 y,

inner face of the sleeveffi's a projectionf, one function of which is toengage a tool-receiving member l@ and cause such member to rotate inunison with the sleeve. The member I0, which is tubular-in general 45contour and .of a size to -t closely in the'sleeve 5, has in it a lug orprojection Il, which engages a flattened portion .of the shank VYQ.atopl tobe receivedapd driven-bythe handelsce- -The niember hasformed-:in it e trensverseslpt I Zfwhicli is 0v intersected by a slot I3which extends to .the end of the member Ill. A. i

.In assembling .the parts the member ,i s intro: duced in positiontotalise the proieptipn of! the sleeve .5to pass throuehptheslbt l?,andepeeee te closed at its upper end vby a cap I5 having apart-,connected with the driving mechanism, toY

resilient extension I6, which latter is attached to the outer face ofthe head by ascrew I'I. v

The novel parts of the handpiecawhile capable of easy modification toadapt them for use in con- `nection with any form of Vtool shank, arepar-,k ticularly adapted foruse with what is recognizedA in the art asthe standard form of this part. Theshank, as shown in Figure 3, has nearone enda recess of flattened portion Ito be engaged by a rotate theshank, and with a circumferential groove I9 to be entered by a member bywhich the shankis prevented from `removal during the time the tool, ofwhich the shank is a part, is in use.

Inasniuch as during the use of a handpiece of thekind described thedriven sleeve 5 and the tool-receiving member Il) are constantly rotatedin contact with portions of the instrument by which they are heldinposition, the consequent ultimate' wear of contacting parts lessens ordestroys the usefulness of handpieces, as ordinarily constructed. Whenthe parts become` worn, even slightly, wabbling of an attached toolensues, rendering satisfactory operation impossible. In order tocompensate for and to adapt the instrument tov take up such wear ofparts, the principal elements of the handpiece are given novel forms inorder that adjustable cone bearings atthe main contacting points may beprovided. '.Ihe end, which may be termed the lower end, ofthetool-receiving member. I is formed with a hollow head or enlargement 20which is cupshaped in general contour, vand inpwhich the inner face ofthe wall is inclined. The lower end 2I of the sleeve 5, which,v whenythe parts are assembled,'bears on the inclined face of the cup -20, isbeveled to correspond to the inner contour of the cap. A cone bearing isfurnished at the upper end ofthe tool-receiving member, by providing theinner face of thercap I5 with a coneshaped projection 22 which entersand bears upon the upper end ofthe ring or collar I4. Any

wear which may occur can readily be ytaken up by turning the ring orrcollar to raise it the required extent. f

In assembling the voperative elements of the handpiece the parts I, 2 ofthe head are separated and the cylinder 5 is introduced into'the lowersection .of the head with the bevel gear 6 in engagement with thepinion 1. The tool-receiving member I0 is then passed upwardlyinto thecylinder. As the member Ill is introduced itis turned to cause theportion I3 of the slot in its upper end to register with the projection9 of the cylinder 5. The member is then pushed up- Wardly untiltheprojection is in line with the portions. The lupper portion of f thehead is then n placed in position, and theparts o f the head are securedinplace by screwing their screw threaded extension's into the shaftcasing 4, When the parts are so placed the projection 22 of the capbears upon the ring or collar I4.

'I'he relative arrangement of the parts is such that when rotation isimparted to the cylinder 5 the tool-receiving member is positivelydriven by reason of the contact of the projection 9 of the cylinder 5with the end of the slot I2. Consequently, when the shank of a tool isintroduced into the tool-receiving member, and the lug Il of the memberenters the indentation I8- of the shank, thertool is Vpositively driven,there being employed no intermediate connecting means involvingfrictional, spring or other unreliable features between the initialdriving means and the tool shank.

So far as I am aware, it is novel, in organizations of the characterherein described, to vutilize by practicable, easily assembled partstheforce exerted to rotate a tool, for the purpose of maintaining a toolin attached operative position. I have herein shownl and described oneform and'disposition of parts to accomplish the purpose; but," ofcourse, I am not limited in this respect. When the described parts areemployed, and the shank of a tool is introduced to bring its indentationI8 to a position to receive the lug II of the toolreceiving member, the,circumferential groove I9 of the tool shank is in line with the portionI2 of the slot in the tool-receiving member. Thus, assuming that theparts are in their'proper initial relative positions, with theprojection 9 of the cylinder 5 extending into the portion I2 of the slotin the tool-receiving member, and in line withI and at the same time toenter andtravel a short distance in the groove I9 of the shank of thetool. When the parts are disposed-as described not only will the tool bepositively driven, but the force exerted to drive the tool effects andmaintains a rigid locking in place of thetool continuously during itsoperation. Y 'I'he advantages Aof these two attainments will belapparent toany oneV who is familiar with the essential requirementsV ofa positive driving of a tool, and of holding means, incapable ofrelease, Vfor maintaining'a tool in place during use. l V Release andremoval of a tool, when the driving power is cut oiis easilyaccomplished by applying slight pressure to the cap I5, holding thetoolreceiving member against rotation, and by turning the head and thecylinder 5 to its initial pos1 tion with the projection 9 in line withthe portion I3 of the slot in the cylinder. In this position, theprojection is removed from the groove I9 of the tool shank and inlinewith the indentationV I8 of the tool, permitting freelwithdrawal fofv`the latter, YIclaim: L v. v

1. A dental handpiece comprising arotatable sleeve, a tool-receivingmember, means'for causing a tool to rotate with the member, and meanswhereby the tool receiving member is caused to rotate with the sleeveand a tool is engaged and prevented from withdrawal from thetool-receivl ing member. y

2. A dental handpiece comprising a rotatable tool-receiving memberhaving an interior lug adapted to engage a tool, and cause the latter'to' rotate in unison with the member, the tool receivingmember beingprovidedwith a transverse slot. a driven sleeve receiving thetool-receiving member, and provided with a projection Yentering andadapted to engage the end of the slot, and to engage and prevent thewithdrawal of a tool.

3. A dental handpiece comprising a rotatable tool-receiving member, alug extending from the member and adapted to engage a tool and cause itto rotate with the member, the tool-receiving member being provided witha transverse slot, and driving means including a projection adapted bothto enter and engage an end thereof, and to engage and prevent thewithdrawal of a tool.

4. A dental handpiece comprising a rotatable tool-receiving memberhaving a transverse slot and a slot intersecting the transverse slot andex tending to the end of the member, and driving means including aprojection adapted to. be passed through the intersecting slot to thetransverse slot, to engage the end of the latter, and to engage andprevent the Withdrawal of a tool located in the member.

5. A dental handpiece comprising a rotatable tool-receiving memben'meansfor positively causing a tool'to rotate with the member, the memberbeing provided with a transverse'slot and with a slot intersecting thetransverse slot and extending to the end of the member, and drivingmeans including a projection adapted to enter the transverse slot'andengage an end thereof, and to engage and prevent the Withdrawal of atool located in the member.

6. A dental handpiece comprising a head, a rotatable sleeve having` atapering end arranged in the head, a hollow tool-receiving memberlocated in the sleeve and having a cup-shaped end having an inclinedinner face, receiving the tapering end of the sleeve, and a cap attachedto the head and having a cone-shaped extension entering and bearing onthe end of the tool-receiving member.

7. A dental handpiece comprising a head, a rotatable sleeve having atapering end arranged in the head, a hollow tool-receiving memberlocated in the sleeve and having an adjustable ring at one end thereof,the other end being cup-shaped and having an inclined inner face,receiving the tapering end of the sleeve, and a cap attached to the headand having a cone-shaped extension entering and bearing on theadjustable ring. y

PERRY R. SKINNER.

